The aim of this study was to estimate the effects of populations and mother trees over some characteristics on pequi (Caryocar brasiliense Camb.) fruits as well as their repeatability coefficient. Data came from two populations with 15 mother trees each, covering three years. The following physical and chemical characteristics were evaluated: total fruit weight; external mesocarp weight; number of putamens per fruit; total weight of putamens; total and average pulp weight; and proportion of the weight of lipids and proteins in relation to pulp weight. Analysis of variance was performed using a nested design model. The effects of mother trees within populations were highly significant for all variables under study, while the effects of populations were not for any characteristic, showing that for populations and mother trees, efforts must be focused on the number of mother trees per population rather than on populations. The estimated repeatability coefficients showed high genetic control for total fruit weight; external mesocarp weight; average weight of putamens; average pulp weight; and proportion of the weight of lipids in relation to pulp weight. Therefore, the expression of these characteristics on descendants, by cloning selected mother trees, is likely to be effective. REPETIBILIDADE DE CARACTERÍSTICAS FÍSICAS E QUÍMICAS EM FRUTOS DE PEQUIRESUMO -O objetivo deste trabalho foi estimar os efeitos de populações, matrizes e do coeficiente de repetibilidade em frutos de pequizeiro (Caryocar brasiliense Camb.). Foram coletados dados de duas populações, por três anos consecutivos, das seguintes características: massa massa total do fruto; massa do mesocarpo externo; número de putâmens por fruto; massa total e média de putâmens; massa total e média da polpa; e a proporção da massa de lipídeos e proteínas em relação à massa total da polpa. A análise de variância foi feita usando-se um modelo de classificação hierárquica. Os efeitos de matrizes dentro de populações foram altamente significativos para todas as características estudadas, ao passo que os efeitos destas populações não o foram para nenhuma característica, evidenciando que no dimensionamento de testes de populações e progênies, deve-se optar pelo maior número de matrizes por população em detrimento do número de populações. As estimativas de repetibilidade encontradas permitem inferir um alto controle genético para as características massa total do fruto; massa do mesocarpo externo; massa média de putâmens; massa média da polpa; e teor de lipídeos e, portanto, uma maior probabilidade de expressão destas características nos descendentes clonais de matrizes selecionadas. Termos para indexação: Caryocar brasiliense, coeficiente de repetibilidade, matrizes.1 (Paper 209-15).

The study of the genetic and phenotypic variability of the populations of Caryocar brasiliense Camb. assists in strategies for conservation and breeding of the specie. The objective of this work was to characterize the genetic diversity through the physical characteristics of pequi fruits of two populations through uni and multivariate analysis, as well as the implications in their domestication and breeding. Fruits were harvested from 20 mother trees (ten fruits per mother tree) from two populations in the state of Minas Gerais (Curvelo and São Gonçalo do Rio Preto Municipalities) during the years 2010, 2011 and 2012. The data were submitted to analysis of variance using a hierarchical classification model. An analysis of clusters and main components was used for studying the divergences. The effects of the populations were not significant for all the characters analyzed in isolation. The gathering of pequi mother trees shown by multivariate analysis did not correspond to the grouping established by the populations. Selection for breeding and/or preservation purposes should concentrate efforts on fewer populations with larger numbers of mother trees per population. Selection of mother trees with higher fruits and thicker pulp fruits among them, even by visual evaluations only, is recommend in sampling mother trees for breeding purposes.

The development of techniques for rapid and uniform emergence of seeds is the alternative to the diversification of citrus rootstocks that were little used due to low vigor compared to 'Rangpur' lime, the main rootstock used in Brazil, but it has shown susceptible to serious disease problems, such as the citrus sudden death (CSD). The addition of the hydrogel polymer to the substrate can increase the uniformity of seed emergence and reduce the time for the production of rootstocks due to the increase in water availability. Thus, the study was done to evaluate the formulation of the substrate with the hydrogel polymer on the uniformity of emergence and early growth of citrus rootstocks. The factorial scheme 3 × 2 × 2 was used, with the factors: Three rootstocks ['Rangpur' lime (Citrus limonia Osbeck), Poncirus trifoliata (L.) and 'Sunki' mandarin (Citrus sunki Hort. ex Tanaka); two formulations of substrate (with and without 0.4 g per container of Hidroplan-EB/HyB-M ® polymer and two environments (greenhouse with an average maximum temperature of 36.6°C and minimum of 17.2°C and growth chamber programmed with temperature to 25°C and a photoperiod of 12 h, distributed in a completely randomized design with four replications and 35 seeds per plot. The emergency velocity index (EVI), the percentage of emergence and early growth of rootstocks were evaluated. Data were subjected to analysis of variance and the means were compared by Tukey test at 5% of probability. The addition of the polymer to the substrate favored the percentage of emergence and EVI of 'Rangpur' lime and of mandarin 'Sunki' seeds in the growth chamber. The 'Rangpur' lime was the rootstock which presented the highest percentage of emergence and uniformity in both environments. The addition of the hydrogel polymer to substrate favored initial growth of citrus rootstocks.